摘要 |
A data clock signal for data in an incoming signal is generated by means of a clock recovery module. The incoming signal consists of a data burst having a periodic preamble followed by a data sequence. The clock recovery module comprises a first clock generator, a sampling device, a correlator, a control unit and a time registration device. The clock generator generates a clock signal having a first clock frequency which is a factor N higher than the frequency of the preamble. The sampling device samples the incoming signal at the first clock frequency. The correlator correlates the sampled signal with a predefined correlation word, the correlation between the incoming signal and the correlation word being represented as a correlation signal in the form of a series of discrete correlation signal values. The control unit detects local extreme values for the correlation signal. The time registration unit forms a status value upon detection of local extreme values in the correlation signal and in response to the associated clock pulses in the clock signal. The control unit generates the data clock signal in response to the clock signal from the first clock generator and the status value of the time registration unit.
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